Shasta County Sheriff's deputies investigate the scene of a triple homicide Wednesday, in Shingletown, Calif. / AP/Andreas Fuhrmann, Record Searchlight

by USA TODAY

by USA TODAY

PETROLIA, Calif. (AP) - Law enforcement officials hunting a man suspected of killing his wife and two young daughters in Northern California have sought help from neighboring agencies.

In an ongoing search, officers from at least a dozen state and federal law enforcement agencies fanned out on Friday across an area of rugged terrain along California's remote north coast where they believe 45-year-old Shane Franklin Miller has taken cover.

Miller, considered armed and extremely dangerous, knows well the tree-lined canyons of Humboldt County where he grew up. Investigators found his pickup truck abandoned near Petrolia, about 200 miles west of the home that Miller shared with his wife, Sandy, 34, and daughters, Shelby, 8, and Shasta, 5.

"It's very strategic how we're moving through that forest area," said Lt. Dave Kent of the Shasta County Sheriff's Office.

Miller is suspected of slaying his family Tuesday night in the rural community of Shingletown, then fleeing to Humboldt County, where low fog and dense brush offer plenty of cover. His mother told the Associated Press she had no idea whether her son and daughter-in-law had suffered marital problems or why Miller might turn on his family.

Kent said detectives continue to search the home where the killings occurred for evidence and clues as to where Miller might have been headed.

In 1996, Miller was convicted of felony cultivation of marijuana in a county known worldwide for the high quality pot grown in the same hard-to-reach forests authorities now are combing.

In 2002, Miller was charged with making and selling marijuana for distribution, being a felon in possession of a firearm, possessing a machine gun and money laundering, according to court records. He pleaded guilty to being a felon in possession of a gun and served 46 months in federal prison for being a felon in possession of a firearm, court records show.

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